Financial Risk Management Activities (Schedule Of Net Notional Volume For Open Derivative Contracts) (Detail) $ / mwh in Millions, $ / DTH in Millions	6 Months Ended	9 Months Ended
	Jun. 30, 2021 $ / mwh $ / DTH	Sep. 30, 2020 $ / DTH $ / mwh
Natural Gas Dth [Member]
Derivative [Line Items]
Net notional volume of derivative transactions | $ / DTH	232	321
Electricity MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	(70)	(66)
FTRs MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	30	20
PSEG [Member] | Natural Gas Dth [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	0	0
PSEG [Member] | Electricity MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	0	0
PSEG [Member] | FTRs MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	0	0
PSEG Power [Member] | Natural Gas Dth [Member]
Derivative [Line Items]
Net notional volume of derivative transactions | $ / DTH	232	321
PSEG Power [Member] | Electricity MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	(70)	(66)
PSEG Power [Member] | FTRs MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	30	20
Public Service Electric and Gas Company [Member] | Natural Gas Dth [Member]
Derivative [Line Items]
Net notional volume of derivative transactions | $ / DTH	0	0
Public Service Electric and Gas Company [Member] | Electricity MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	0	0
Public Service Electric and Gas Company [Member] | FTRs MWh [Member]
Derivative [Line Items]
Net notional volume of derivative transactions	0	0